Figure 3.

Mechanistic depiction of Tat induced neuronal and astrocytic apoptosis: Tat protein taken up by bystander cells induces the formation of nNOS that leads to the formation of Nitric Oxide (NO), significant release of calcium from intracellular calcium stores that triggers other downstream mediators of apoptosis in both neurons and astrocytes. Apoptosis of both cell types (neurons and astrocytes), as well as others like axonal/dendritic shrinkage, causes a neurocognitive decline in HIV-infected individuals.